1. Field of the Invention
The present invention relates to optical disc recording and reproducing technology, and more particularly, to a method of verifying the defect management area information of a recordable and reproducible optical disc, and a test apparatus for performing the same.
2. Description of the Related Art
Digital versatile disc-random access memory (DVD-RAM) discs have a defect management function of replacing defective areas with normal recordable areas and storing information necessary for the defect management in a portion referred to as a defect management area (DMA) thereon. DMA information is repeatedly recorded in four portions on a disc: two portions in a lead-in area and two portions in a lead-out area. DMA information is composed of a disc definition structure (DDS), a primary defect list (PDL) and a secondary defect list (SDL). DMA information includes information on a spare area and important information on the start logical sector number of each zone, in addition to information on defects, which are detected during certification performed while a disc is being initialized or during use of a disc.
Some information included in the DMA can be immediately read and used. On the other hand, the DMA includes information which varies with the positions and the number of defects on a disc. That is, some information, for example, the position information of the start logical sector number of each zone or the position information of a first logical sector number, can be obtained only by performing complex computation according to a given algorithm based on defect information registered in the DMA.
Since such DMA information is closely related to a physical data recording position, a recording medium such as an optical disc, which can be used in a given recording and reproducing apparatus even if DMA information on the disc has been generated or updated in another recording and reproducing apparatus, may have a compatibility problem between the recording and reproducing apparatuses when the DMA information is wrong. To overcome this problem, an apparatus and method of verifying that a recording and reproducing apparatus correctly reads DMA information from a disc and correctly records DMA information on the disc is desired.
To solve the above problem, a first object of the present invention is to provide a method of verifying that defect management area (DMA) information on a disc is correctly generated and updated in an optical disc recording and reproducing apparatus which detects defects on the disc and records information on the defects in a DMA.
A second object of the present invention is to provide a method of verifying that defect management area (DMA) information on a disc is correctly generated and updated in a recording and reproducing apparatus for repeatedly recordable and reproducible DVD-RAM discs, which detects defects on the disc and records information on the defects in a DMA.
A third object of the present invention is to provide a method of verifying that an optical recording and reproducing apparatus always reads and processes defect information properly, under the same conditions without being influenced by an actual state of a disc having defect information, using a test disc containing predetermined defect information which does not have any relation with actual defects.
A fourth object of the present invention is to provide a test apparatus for verifying that defect management area (DMA) information on a disc is correctly generated and updated in an optical disc recording and reproducing apparatus which detects defects on the disc and records information on the defects in a DMA.
A fifth object of the present invention is to provide an apparatus for testing an optical recording and reproducing apparatus to verify that it always reads and processes defect information properly, under the same conditions without being influenced by an actual state of a disc having defect information, using a test disc containing predetermined defect information which does not have any relation with actual defects.
Additional objects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
To achieve the above and other objects of the invention, there is provided a method of verifying that DMA information is properly generated or updated in a recording and reproducing apparatus which records or reproduces information on or from an optical disc with DMA information. The method includes selecting one among a plurality of test modes for verifying the DMA information and setting a test reference according to the selected mode, generating test information from the DMA information, which is generated or updated by the recording and reproducing apparatus to be tested, according to the verification test mode, and executing the test for verifying the test information using the test reference in the selected mode.
To achieve the above and other objects of the invention, there is also provided an apparatus for testing a recording and reproducing apparatus which records or reproduces information on or from a recording and reproducing optical disc with DMA information to check whether the DMA information is properly generated or updated. The apparatus includes a modified drive which generates test information from the generated/updated DMA information of a test disc, which is obtained after the recording and reproducing apparatus processes the test disc with a DMA mirror file corresponding to a selected mode among a plurality of DMA information verification test modes for verifying the DMA information in the selected mode; and a verifier which compares the test information with predetermined test information of the selected mode to verify the test result.